Effect of sowing dates on yield and yield-attributes of some sunflower hybrids

To determine the optimum sowing date for some sunflower hybrids i.e. A11 x Rf7, A11 x Rf9, A12 x Rf9, A8 x Rf10, A11 x Rf10, A8 xRf12, A9 x Rf12, A15 x Rf12, A2 x Rf20 and the check variety Sakha 53, along with to assess their genetic variability and to determine selection criteria for improving their yield. These materials were sown at four adjacent field represent four sowing dates i.e. 20th of April, 20th of May, 20th of June and 20th of July using randomized complete block design with three replications at the experimental Farm of El Mattana Agricultural Research Station, (latitude of 25.17o N and longitude of 32.33o E), Luxor Governorate, during the two successive summer seasons 2018 and 2019. Results revealed that early sown plants on 20th of April had high yield potential compared to other sowing dates. The promising sunflower hybrid for seed yield feddan-1 and more yield attributes was A12 x Rf9 when sown on 20th of April and across sowing dates, whereas A15 x Rf12 when it sown on 20th of July and across sowing dates was the best for seed oil content. Considerable genetic variability was detected among sunflower genotypes, and hence the selection would be effective to genetic improvement of seed weight plant-1 for these materials, which can be achieved through selecting genotypes having the largest head diameter and the heaviest weight of 100-seed.

An investigation into the current utilisation and prospective of renewable energy resources and technologies in Libya

With the increase in energy demand and the international drive to reduce carbon emission from fossil fuel, there has been a drive in many oil-rich countries to diversify their energy portfolio and resources. Libya is currently interested in utilising its renewable energy resources in order to reduce the financial and energy dependency on oil reserves. This paper investigates the current utilisation and the future of renewable energy in Libya. Interviews have been conducted with managers, consultants and decision makers from different government organisations including energy policy makers, energy generation companies and major energy consumers. The results indicate that Libya is rich in renewable energy resources but in urgent need of a more comprehensive energy strategy and detailed implementation including reasonable financial and educational investment in the renewable energy sector

Effect of mutation and vaccination on spread, severity, and mortality of COVID-19 disease

Coronavirus disease 2019 (COVID-19) has had different waves within the same country. The spread rate and severity showed different properties within the COVID-19 different waves. The present work aims to compare the spread and the severity of the different waves using the available data of confirmed COVID-19 cases and death cases. Real-data sets collected from the Johns Hopkins University Center for Systems Science were used to perform a comparative study between COVID-19 different waves in 12 countries with the highest total performed tests for severe acute respiratory syndrome coronavirus 2 detection in the world (Italy, Brazil, Japan, Germany, Spain, India, USA, UAE, Poland, Colombia, Turkey, and Switzerland). The total number of confirmed cases and death cases in different waves of COVID-19 were compared to that of the previous one for equivalent periods. The total number of death cases in each wave was presented as a percentage of the total number of confirmed cases for the same periods. In all the selected 12 countries, Wave 2 had a much higher number of confirmed cases than that in Wave 1. However, the death cases increase was not comparable with that of the confirmed cases to the extent that some countries had lower death cases than in Wave 1, UAE, and Spain. The death cases as a percentage of the total number of confirmed cases in Wave 1 were much higher than that in Wave 2. Some countries have had Waves 3 and 4. Waves 3 and 4 have had lower confirmed cases than Wave 2, however, the death cases were variable in different countries. The death cases in Waves 3 and 4 were similar to or higher than Wave 2 in most countries. Wave 2 of COVID-19 had a much higher spread rate but much lower severity resulting in a lower death rate in Wave 2 compared with that of the first wave. Waves 3 and 4 have had lower confirmed cases than Wave 2; that could be due to the presence of appropriate treatment and vaccination. However, that was not reflected in the death cases, which were similar to or higher than Wave 2 in most countries. Further studies are needed to explain these findings

High-voltage pulse generator based on sequentially charged MMC-SMs operating in a voltage-boost mode

Pulse forming networks and Marx generators are the classical rectangular waveform pulse generators (PGs). They are inflexible and their capacitors must be fully charged to the required voltage from 0V before delivering each high-voltage (HV) pulse. They are only able to generate unipolar pulses; if bipolar pulses are sought another generator fed from a negative supply voltage is added. Recently, several power electronics based PGs have been proposed. This paper presents an HV power electronics based PG, which is based on Half-Bridge Modular Multilevel Converter (HB-MMC) sub-modules (SMs) charged sequentially in a voltage boost mode. Each SM capacitor and main switch form a boost converter with the charging input supply and inductor. As a result, all SM capacitors are charged to a voltage greater than the input. During the discharging process the SM capacitors are connected in series, producing a rectangular HV pulse across the load. The proposed charging method allows a reduction in the converter footprint in comparison with recently proposed MMC sequentially charged PG topologies. Although only rectangular pulse waveforms are sought in this paper, a SM capacitor voltage balance method allows multilevel pulse generation. The viability of the proposed converter is confirmed by MATLAB/Simulink simulation and scaled-down experimentation

Anaesthetic Considerations in Gastrointestinal Endoscopies

Gastrointestinal endoscopy has become fundamental procedure for diagnosis and treatment of gastrointestinal tract diseases. Generally, the gastrointestinal endoscopy is minimally invasive procedure. However, it can cause considerable amount of discomfort and pain which make the procedure unsafe, complicated and refusal of follow up procedures if done without safe sedation. The sedation is required to alleviate anxiety, provide analgesia, amnesia and to improve endoscopic performance specifically in therapeutic procedures. The safe administration of sedative and analgesic medications, irrespective of the regimen used, requires knowledge of the individual needs of patients. The combination of benzodiazepines and opioids is now the most widely used sedation regimen for sedation in gastrointestinal endoscopic procedures. Generally, sedation for gastrointestinal endoscopy is considered safe, however, it has the potential for serious complications. Therefore, endoscopist should assess the patients properly before the endoscopy as well as should be aware of all possible complications and the risk factors. Furthermore, skilled staff and emergency equipment should be available in endoscopy suit. This chapter discuss in details all the aspects of safe procedural sedation during GI endoscopies

Wireless Electromagnetic Radiation Assessment Based on the Specific Absorption Rate (SAR): A Review Case Study

Employing Electromagnetic Fields (EMFs) in new wireless communication and sensing technologies has substantially increased the level of human exposure to EMF waves. This paper presents a useful insight into the interaction of electromagnetic fields with biological media that is defined by the heat generation due to induced currents and dielectric loss. The Specific Absorption Rate (SAR) defines the heating amount in a biological medium that is irradiated by an electromagnetic field value. The paper reviews the radio frequency hazards due to the SAR based on various safety standards and organisations, including a detailed investigation of previously published work in terms of modelling and measurements. It also summarizes the most common techniques utilised between 1978 and 2021, in terms of the operational frequency spectrum, bandwidth, and SAR values